The 3D® Quad-Action Mandibular Appliance is a simple, inexpensive alternative to more than 20 different sagittal and transverse removable appliances. This versatile appliance can produce unilateral or bilateral rapid arch expansion or contraction; expand or contract bicuspid position; advance or retract incisors; and can rotate, tip, or torque the molars. The adjustments necessary to accomplish these movements are easily made, since the arch wire is simple to remove from the molar bands.